// B2009 write by cn_ryh
#include <iostream>
using namespace std;
int a_and_b(int a, int b, int c)
{
    return (a + b) / c;
}
int main()
{
    int a;
    int b;
    int c;
    cin >> a >> b >> c;
    cout << a_and_b(a, b, c) << endl;
    return 0;
}
